Collapsible rolling support stand

ABSTRACT

A collapsible folding stand for use with a portable table saw or other object that is attached to the stand and is capable of being manipulated between open and closed positions. In the closed position, the stand is generally vertically oriented with the object attached to a top frame. To open the stand a locking mechanism is released which enables a folding mechanism supporting the top frame to unfold in a manner whereby the rear legs having wheels that separate from forward side struts which contact the ground, with the center of gravity of the object being positioned between the wheels and the front ground contact points so that the weight of the object tends to separate the same and bring the top frame into a generally horizontal position. To move the rolling stand to its closed position, the user needs only to lift the handle and the top frame will then move to its generally vertical closed position.

BACKGROUND OF THE INVENTION

The present invention generally relates to rolling support stands.

Rolling hand trucks or support stands for large and/or heavy objectshave been known for decades and are useful for transporting such objectsfrom one location to another. Some of such known support stands arecollapsible to some degree and many different designs of the hand trucksor rolling support stands are particularly suited for specific uses.While such products may be used in many different industries andapplications, one noteworthy use is that of transporting objects, suchas portable table saws, miter saws and the like to and from constructionsites.

In the home building trade, carpenters generally have table saws as wellas other types of saws that are brought to a jobsite every day in thetradesman's truck or are stored in a secure location at the jobsite andmust be removed from the truck or stored location and be set up on thejobsite while work is being done. At the end of the work day, thetradesman must pack up the saw and return it to his truck or securelocation for safe keeping. Because such tools are valuable, they cannotbe left unattended overnight without a significant risk of theft.

There is also an issue of setting up the saw at the worksite. Eventhough early prior art roll stands or hand trucks may help the tradesmanto move the saw to the desired location, it was often necessary to havea table or other surface, such as wooden planks resting on saw horses orthe like to bring the saw to a convenient working height during use.Although more recent designs have evolved which have a rolling standthat can be unfolded to support the saw at an appropriate workingheight, all known designs that double as a stand require the tradesmanto lift a substantial portion of the weight of the saw which istypically relatively heavy.

Most portable table saws are very similar in design to standard tablesaws except they do not have a stand with legs beneath them and must besupported by a separate structure. Such portable table saws are ruggedcommercial tools that are built for an extended useful life and aretherefore relatively heavy. Typical table saws of this type may weigh 60pounds or more. While most tradesmen can usually lift 40-60 pounds, suchexertion is inconvenient and perhaps dangerous in certain circumstances.

Other types of stands may unfold using a spring biasing mechanism thatis released and which then supplies a major force tending to place thestand with the saw attached to it in its proper working generallyhorizontal position. However, stands of this type may be dangerous ifthe folded stand has the mechanism released when the weight of the sawis not over the stand mechanism. If there is no load on the mechanism,it can unfold very rapidly which can be quite dangerous if a tradesmanor any other person is struck by the mechanism.

SUMMARY OF THE INVENTION

Several embodiments of the present invention comprise a collapsiblefolding stand for use with a horizontally oriented object such as aportable table saw that is attached to the stand wherein the stand has afront and a rear portion and is capable of being manipulated betweenopen and closed positions. In the closed position, the stand isgenerally vertically oriented with the object attached to a top frame.The stand has a folding mechanism with a pair of wheels which enable auser to roll the stand with the attached object from one location toanother. When the stand is in the desired location, a locking mechanismis released which enables a folding mechanism supporting the top frameto unfold in a manner whereby the rear legs having wheels that separatefrom forward side struts which contact the ground, with the center ofgravity of the object being positioned between the wheels and the frontground contact points so that the weight of the object tends to separatethe same and bring the top frame as well as the object into a generallyhorizontal position.

To move the rolling stand to its closed position, the user needs only tolift the handle and the top frame will then move to its generallyvertical closed position where the latching mechanism can then beengaged. Because of the mechanism advantage of the folding mechanism,moving between the open and closed positions in either directionrequires very little effort by the user.

Selected embodiments can have a tension spring attached to frame memberswhich is placed in tension only when the stand is in its open positionwith the force of the spring further aiding movement of the stand to itsclosed position. A smaller almost zero force may only be required by theuser to close the stand.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a first preferred embodiment shown with aportable table saw attached to its top frame with the rolling standbeing in its locked closed position;

FIG. 2 is a side view of the first preferred embodiment and table sawshown in a partially opened position, particularly the position that isachieved after the latching mechanism is released;

FIG. 3 is a view of the first preferred embodiment and table saw withthe stand being further opened;

FIG. 4 is a side view of the first preferred embodiment and table sawfully opened;

FIG. 5 is a rear and side perspective view of a second preferredembodiment of a collapsible stand which represents a more stylized andcommercial version of the first preferred embodiment shown in FIGS. 1-4;

FIG. 6 is a top view of the second preferred embodiment;

FIG. 7 is a side view of the second preferred embodiment;

FIG. 8 is a rear end view of the second preferred embodiment;

FIG. 9 is a diagrammatic side view of a third preferred embodiment shownwith an object attached to the top frame and shown in its closedposition;

FIG. 10 is another side view of the third preferred embodiment shown inits opened position;

FIG. 11 is a diagrammatic side view of a fourth preferred embodimentshown with an object attached to the top frame and shown in its closedposition;

FIG. 12 is another side view of the fourth preferred embodiment shown inits opened position;

FIG. 13 is a diagrammatic side view of a fifth preferred embodimentshown with an object attached to the top frame and shown in its closedposition;

FIG. 14 is a diagrammatic side view of a fifth preferred embodimentshown in its partially opened condition;

FIG. 15 is another side view of the fifth preferred embodiment shown inits opened position;

FIG. 16 is a diagrammatic side view of a sixth preferred embodimentshown with an object attached to the top frame and shown in its closedposition;

FIG. 17 is a diagrammatic side view of a sixth preferred embodimentshown in its partially opened condition;

FIG. 18 is another side view of the sixth preferred embodiment shown inits opened position;

FIG. 19 is a diagrammatic side view of a seventh preferred embodimentshown with an object attached to the top frame and shown in its closedposition;

FIG. 20 is another side view of the seventh preferred embodiment shownin its opened position;

FIG. 21 is a side view of a portion of the seventh embodiment,particularly illustrating the gear mechanism that interacts with thefirst member, the second member and the link member; and

FIG. 22 is a perspective view, particularly illustrating the shape ofthe first member and the interconnection with the second member and thelink member.

DETAILED DESCRIPTION

The various embodiments of the collapsible rolling stand of the presentinvention have the common design feature that includes a top frame uponwhich an object such as a table saw or the like can be attached and afolding mechanism that includes at least first and second members thatare pivotable relative to one another and which resemble a scissormovement, with the center of gravity of the object that is attached tothe top frame being located between the ground contacting ends of eachof the first and second members. This enables the weight of the objectto assist the unfolding of the stand which causes the object to movefrom a generally vertically oriented position to a generally horizontalposition. Because the center of gravity of the object is between theground contacting ends of the first and second members, the stand can beeasily folded back to the collapsed generally vertical position withoutsignificant exertion by a user performing either operation. Unlike manyprior art rolling stands, the user does not have to provide any heavylifting in order to set up or break down the stand with the objectattached to it. In this regard, a user can completely set up or knockdown the stand by holding the handle and gently urging it in onedirection or the other to open or close it. It is only necessary tomanipulate a locking mechanism to release it from a closed position andto lock it when it has been moved from an opened position to its closedposition.

Turning now to the drawings and particularly FIGS. 1-4, a firstpreferred embodiment of a collapsible rolling stand is shown at 10 andhas a portable table saw 12 that is attached to the stand. The stand 10has a top frame 14 which is comprised of two side members 16 and two endmembers 18.

The table saw 12 is commonly referred to in the trade as a portabletable saw in that it does not have legs or a particularly deep lowerframe portion. The saw 12 is intended for commercial use and is oftenset up at a job site such as where a house is being constructed so thatcarpenters or other tradesman can cut lumber as needed during theconstruction. The saw 12 has bolt holes (not shown) at the outer cornersof the base of the saw through which bolts are placed to both the sawonto the top frame 14 of the stand 10. The bolts may fit into openingsin the side members 16 or the end members 14 or to cross struts that maybe added to the top frame for providing additional strength and/or asuitable structure to which the saw 12 can be attached.

The rolling stand 10 has a folding mechanism, indicated generally at 20,which supports the top frame 14 referring to FIGS. 1-4, the buildingmechanism has opposite sides that are substantially similar to oneanother and for that reason will be given the same reference numbers forthe individual components of each side. Each side has a main side strut22 that extends from a pivot connection 24 to the top frame 14 and alsodownwardly to an end 26 that contacts the ground. The lower portion ofmain side strut 22 has a transverse platform extension 28 that isconnected to the other side by a front end bridge 30 and a cross brace32. The platform extensions 28 and front end bridge 30 and cross brace32 define a platform or shelf on which the user may place a tool box orother object. It should also be understood that a sheet material may beconnected to the components 28, 30 and 32 so that objects that aresmaller than these components may easily be carried on the platform.

A second cross brace 34 interconnects the main side struts 22 to providestrength at the mid portion of the length of the side struts 22 and toprovide a stop surface for at least partially limiting the openingmovement no further than is shown in FIG. 4. Additional strength is alsoprovided by an angled auxiliary side strut 36 that has a generallytransverse extension 38, a locking handle 40 that has a pin extending inan opening 39 through the extension 38 that is spring biased so that thehandle 40 is biased toward the extension 38. It should be understoodthat a handle 40 could be provided only on one side if desired. Thestand has a rear leg 42, with an angled upper leg extension 44 and alower transverse extension 46 to which a wheel 48 is attached. The wheel48 is mounted on an axle that is either bolted or welded to theextension 46. A rear end bridge 50 interconnects the rear legs 42 andthe rear legs are connected to the side strut 22 by a connection point52 so that the rear leg can pivot relative to the side strut 22.

A flat curved sheet 41 is attached to both the extension 44 and theadjacent portion of the rear leg 42, preferably by welding, although itcan be attached in other ways that are well known to those of ordinaryskill in the art. The sheet is preferably about 2 millimeter thick steelthat is attached to be coplanar with the inside surface of the extension44 and rear leg 42. The rod portion of the handle 40 is configured toengage an aperture 43 in the sheet 41 when the stand is fully open asshown in FIG. 4. This firmly locks the stand so that it can withstandforces that may be applied to it during use of the saw by a user. Whenthe stand is in its closed position, the rod portion of the handle 40aligned to extend past the right edge of the extension 44 as shown inFIG. 1, which prevents the rear leg 42 from rotating in the clockwisedirection around pivot connection 52. In other words, the stand islocked in its closed position in this manner.

A handle 54 extends from side arms 56 that are connected to the mainside strut 22 as well as the auxiliary side strut 36 and it extends awayfrom the side struts several inches so that the hands of the user arenot interfered with by the end member 18. The handle 54 is positioned atthe rear end of the stand so that when it is in its closed position, theuser can roll the stand and the attached table saw easily in much thesame manner as a hand truck is used. A link member 58 is pivotallyconnected to the leg extension 44 at connection 60 and to the top frameside member 16 by connection 62.

To open a closed rolling stand 10 which is shown in FIG. 1, the operatorpulls the handles 40 so that the main side strut 22 and rear leg 42 canpivot relative to one another around the pivot connection 52. When thathappens, the wheels will normally separate a short distance as a resultof the weight of the stand and saw causing the rear leg and wheel tomove to the left as shown in the drawings. In this regard, when thisembodiment of the stand is in the position shown in FIG. 1, the wheels48 preferably extend slightly lower than the bottom of the extension 28,so that the contact point 26 is not touching the ground. When thehandles 40 are released, the saw then will move to the position shown inFIG. 2 where the platform extension 28 is flat on the ground and thewheels are spaced away from the contact point 26. From the positionshown in FIG. 2, a user merely needs to pull on the handle toward himand to the left as shown in FIG. 2 which will cause the rear leg 42 torotate in a clockwise direction relative to the side strut 22 and as itis moved, the extension 44 of the rear leg will similarly rotate in aclockwise direction and cause the link member 58 to move the right endof the top frame upwardly as is shown by comparing the position of thestand in FIG. 3 relative to FIG. 2. As the handle is moved farther tothe left and boundwardly, the top frame is brought into a horizontalposition which is stopped by the contact between the leg extension 44and the cross brace 34 and the pin portion of the handle 40 engages theopening 43 in the sheet 41 as is clearly shown in FIG. 4. In thisposition, the table saw is ready for use once a source of power isprovided to it. A significant advantage of the rolling stand 10 is thefact that the center of gravity of the saw is located between thecontact point 26 and the wheels very early in the process of opening thestand and because of that, the weight of the saw assists in theunfolding of the saw to its open position which minimizes the effortthat is required by the user to open the stand.

To close the stand, the operator merely needs pull the handle 40 andpull upwardly on the handle 54 and the rear legs 42 will rotate in acounterclockwise direction relative to the main side strut 22 and movein the reverse sequence from FIGS. 4 to 1 whereupon pin of the handle 40engages the rear leg to lock the stand in its closed position. Becauseof the design of this embodiment, there is very little effort requiredto move the stand from its open to its closed position, but amodification can be made to this embodiment by placing a tension spring64 between the main side strut 22 and the rear leg 42 which will providean auxiliary biasing force tending to both the stand from its open toits closed position. An axial spring provided at the connected point 52may also be used as an alternative to the tension spring 64.

The spring 64 can be designed so that it provides sufficient biasingforce tending to rotate the rear leg in a counterclockwise directionrelative to the main side strut 22 so that only a very small force,i.e., one approaching zero, may be necessary to close the stand from itsopen position. It should also be understood that a spring may beprovided on each side of the stand to provide a more balanced closingforce. Unlike some prior art rolling stands, the configuration of thespring in this embodiment only loads the spring when it approaches theopen position. Other prior art mechanisms include a spring openingmechanism that once released causes the stand to unfold, with the forceof the mechanism being substantial. When the stand is in the properposition this usually does not create a problem, but if the stand is notproperly positioned, release of the mechanism can cause it to rapidlyunfold with sufficient speed and energy that it can easily injure theuser if the user is in position to be struck. That condition isvirtually impossible in the illustrated embodiment for the reason thatthe spring is never loaded until it approaches its open position.

The handle 54 is also positioned at an angle relative to the link of theside strut 22. This provides a convenient contact point for the stand ifa user wishes to load the stand and saw into the cargo area of a truckor van. The user can merely wheel the stand to the truck, turn it aroundso that the handle is near the cargo truck surface and it can be rotatedtoward the truck so that the handle provides a sliding surface and theuser can then pick up the cart by the front end bridge 30 and load itinto the cargo area.

The first preferred embodiment 10 is shown to have been constructed ofhollow steel extrusions that are welded together and with the pivotconnections comprising bolts extending through the illustratedcomponents. A more substantial connection with bearings or otherfriction reducing elements can be used as are known to those of ordinaryskill in the art. The side arms 56 are shown to be firmly attached byscrews or bolts. The nature of the attaching and pivoting connectionscan vary depending upon obvious engineering design that is well know tothose of ordinary skill in the art.

A second preferred embodiment which represents a sleeker, smootherdesign that may be less expensive to manufacturer is shown in FIGS. 5-8.In this embodiment, a rolling stand, indicated generally at 100, isshown without an object attached to it, but it has a top frame,indicated generally at 102, that comprises side members 104 as well asan end member 106 to which two flat mounting plates 108 and 110 areattached. In this embodiment, the stock frame 102 is made of a circularstock and the side members 104 and the end member 106 are a unitarystructure that is bent to form the top frame. The plates are preferablymade of 2 mm. thick sheet, but may be a thinner or thicker steel stockor can be made of other metal. An important criterion is that it shouldbe sufficiently strong that a saw or other object can be bolted toeither pre-made holes or holes that are drilled in the plates when thesaw or other object is attached to it.

The embodiment 100 also has a folding mechanism 112 that includes a mainside strut 114 that is pivotally attached to the top frame by pivotconnection 116 and extends downwardly to a ground contact 118. Aplatform extension 120 is also provided and it has a end bridge 122 thatinterconnects the platform extension of each side. A metal platform bed124 is connected to the end bridge 122 and platform extensions 120. Italso has a horizontal portion 126 and a rear portion 128 that isgenerally perpendicular to the plane of the platform 124. These sheetsurfaces provide support for carrying other articles or equipment that auser may have, such as a tool box, lunch box, radio or the like. Themain side strut 114 extends upwardly to the connections 116 beyond whichthey are formed into generally transverse handle extension 130 thatmerges with a curved handle 132. The handle has a general upward curveas shown in the drawings, this is not only ergonomically convenient, butalso defines two lower contact points 134 that may facilitate the standbeing loaded onto an elevated platform such as a cargo floor of a truckor van.

This embodiment also has a rear leg 136 with a leg extension 138 that isangled approximately 70°, but which could be a greater or lesser angledepending upon other relationships that are made in the design. The rearlegs 136 also have a downwardly generally perpendicular leg extension140 to which a wheel 142 is attached to each side thereof. A rear endbrace 144 is provided to interconnect the rear leg extensions 1140. Therear leg 136 has a curved auxiliary support member 146 that is attachedto the rear leg 136 and the leg extension 138 by preferably being weldedthereto and this support member has a inwardly directed stop member 148that is positioned to engage the main side strut 114 when it reaches itsopen position as best shown in FIG. 5. The rear leg 136 is pivotallyconnected to the side strut 114 by pivot connection 150. A link member152 is also provided in this embodiment and it has a pivot connection154 to the end of the rear leg extension 138 and a pivot connection 156for connecting to the side member 104 of the top frame. The operation ofthis embodiment is substantially similar to the first embodiment shownin FIGS. 1-4.

When the rolling stand 100 shown in its open position in FIG. 5 is to bemoved to its closed position, the handle 134 must be raised to move theside strut 114 upwardly. The rear leg 136 will then pivot in a clockwisedirection around pivot point 150 so that the wheel 142 will begin toapproach the lower contact point 118 during the closing operation. Alsothe rear leg extension 136 will move pivot point 154 in a clockwisedirection relative to pivot point 150 and cause the front end of thestand to move downwardly so that end 106 will move in a counterclockwisedirection pivoting around the opposite pivot connection 116, resultingin the end 106 approaching the lower end of the side strut 114. From avertical closed position the opposite series of movements will occur ashas been described with regard to FIGS. 1-4.

A third preferred embodiment is shown in the FIGS. 9 and 10 in asimplified manner, with a rolling stand, indicated generally at 160,having an object 162 attached to it. As with the embodiment in FIG. 1,the object 162 may certainly be a circular saw, miter saw or other tool.The object 162 is attached to a top frame 164 that is not shown indetail, but which would be similar to the top frame 14 of FIG. 1. Therolling stand 160 has a side strut 166 which extends from a upper handleportion 168 to a bottom contact point 170 and the side strut has atransverse platform extension 172 which is fixed with regard to the sidestrut 166. A rear leg 174 having a wheel at its lower end is pivotallyconnected via a pivot connection 178 to the side strut 166. The upperend of the rear leg 174 has a pivot connection 180 to a first linkmember 182 that has a slot 184 and in which the pivot connection 180also can slide along the length thereof. The opposite end of the firstlink member 182 has a pivot connection 186 to a second link member 188as well as to a third link member 191. The second link member 188 hasits opposite end pivotally connected to the top frame 164 by the pivotconnection 190. Similarly, the opposite end of the third link 191 has apivot connection 192 adjacent the lower contact point 170 of the sidestrut 166. The upper end of the side strut 166 is also connected to thetop frame 164 and particularly to a transverse extension 194 wherein apivot connection 196 permits the side strut 166 to rotate relative tothe top frame 164.

To open the rolling stand 160 from the closed position in FIG. 9 to openposition in FIG. 10, the user simply pulls the handle 168 to the rightas shown in FIG. 9 which will cause the side strut 166 to pivot relativeto the lower portion of the rear leg 174 so that the wheel will moveaway from the contact point 170. Simultaneously, the top end of the rearleg will move in a counterclockwise direction or to the left as shown inFIG. 9 and the pivot connection 180 will slide down the slot 184 as themechanism opens. The fist link member 182 will force the pivotconnection 186 in a downward direction as shown in FIG. 9 which willtend to cause the second and third link members 188 and 191 tostraighten out relative to one another and cause the top frame 164 tomove to a horizontal position as shown in FIG. 10. In this openposition, the pivot connection 180 of the rear leg portion will reachthe lower end of the slot 184 which will prevent any further movement tothe left and will thereby hold the top frame 164 and object 162 in thedesired horizontal position.

A fourth embodiment illustrates a rolling stand 200 with an attachedobject 202 that is illustrated in a closed position in FIG. 11 and anopen position in FIG. 12. The rolling stand 200 has a top frame 204 withpivot connection 210 located at the bottom end as shown in FIG. 11. Therolling stand 200 has a main side strut 212 that is pivotally connectedto a transverse extension 214 of the top frame 204 at pivot connection216. The side strut 212 extends downwardly to a bottom contact point 218and has a transverse platform extension 220 that is rigid with regard tothe side strut 212. A rear leg 222 with an attached wheel 224 ispivotally connected by connection point 226 to the side strut. The upperend of the rear leg 222 has a connection point 228 for connecting to afirst link member 230, the other end of which is pivotally connected toa second link 234 and a third link member 236 by pivot connection 238.The other end of the second link member 234 is connected to the topframe 204 by the connection 210 and other end of the third link 236 isconnected to the bottom of the side strut 212 adjacent the contact point218 by pivot connection 240. The upper portion of the side strut 212terminates at a handle 242.

To open the roller stand 200, user will pull the handle 242 to the rightas shown in FIG. 11 which will cause the rear leg 222 below the pivotconnection 226 to rotate in a counterclockwise direction so that thewheel 224 separates from the contact point 240 of the side strut 212.This causes the upper end of the rear leg 222 to move the connection 228left and down thereby moving the first link member downwardly from theposition shown in FIG. 11 and also causing the connection 238 to moveboth the second and third link members 234 and 236 to straighten themrelative to one another while simultaneously moving the top frame 204 toits horizontal position.

A fifth embodiment of the stand is indicated generally at 250, and isshown in FIGS. 13, 14 and 15 together with an object 252 that isattached to a top frame 254 of the stand 250. In this embodiment, a mainside strut 256 is attached to an extension 258 of the top frame 254 witha pivot connection 260 that is also slidable in a slot 262. The upperend of the side strut merges with a handle 264. The side strut 256 alsohas a bottom contact point 266 and a transverse platform extension 268.A rear leg 270 has a wheel 272 attached to the bottom end thereof and ispivotally attached to the side strut by pivot connection 274. At theupper end of the rear leg 270 is a pivot connection 276 that connects toa link member 278 that is pivotally connected to the top frame 254 bypivot connection 280. The connection 276 also includes a stop portion282 that prevents over center movement, i.e., movement beyond theorientation shown in FIG. 15 where the leg member 278 is in line withthe longitudinal axis of the rear leg 270.

To open the embodiment 250 from its closed position shown in FIG. 13 toits completely open position shown in FIG. 15, a user again pulls thehandle 264 to the right which causes relative pivoting movement betweenthe side strut 256 and the lower portion of the rear leg 270 so that thewheel 272 moves away from the contact point 266, which in turn causesthe upper end of the rear leg 270 to rotate in a counterclockwisedirection and move the link member 178 so that it pivots in a clockwisedirection around pivot connection 280 until it is generally aligned withthe lengthwise direction of the rear leg 270 and the stop 282 halts itsfurther movement. While it is shown to be straight relative to the rearleg 270 in FIG. 15, depending upon the relative lengths of the rear legand link member 278 and the position of the pivot connection 274 alongthe side strut 256, the movement of the link member 278 may rotatebeyond what is shown in FIG. 15, and would be similar to that shown inFIG. 18 which has yet to be described.

To close the rolling stand 250 from the open position shown in FIG. 15,it is only necessary to push the handle 264 to the left as shown in FIG.15 while perhaps unlocking the stop 282 if necessary. Further movementof the handle 264 will cause the stand to move toward the closedposition shown in FIG. 13.

A sixth embodiment of the rolling stand is indicated generally at 300and is shown in its closed position in FIG. 16, an intermediate positionin FIG. 17 and an open position in FIG. 18 and is shown with an object302 that is attached to the stand. In this embodiment, the stand 300 hasa top frame 304 with a transverse extension 306 at the forward endthereof which has a slot 308 in which a pivot and sliding connection 310is located. A main side strut 312 is pivotally connected to an extension314 of the top frame 304 by pivot connection 316. The upper end of theside strut 312 merges with a handle 318 and the lower end thereof has aground contact point 320 and a transverse platform extension 322. A rearleg 324 has a wheel 326 connected to the lower portion thereof and theleg is pivotally connected to the side strut at pivot connection 328.The upper end of the rear leg 324 is connected to a link member 330 bypivot connection 332. The other end of the link member 330 is connectedto the extension 306 by the pivot connection 310 previously identified.The pivot connection 332 also has a over center stop member 334 thatlimits the pivoting movement of the rear leg 324 relative to the linkmember 330 essentially to that which is shown in FIG. 18. In thisembodiment, when the stand is to be opened from the closed positionshown in FIG. 16 to the open position shown in FIG. 18, the handle 318is pulled to the right which causes the lower portion of the rear leg324 to pivot around pivot connection 328 and the wheel 326 will beseparated from the contact point 320. As this motion occurs, the pivotconnection 332 at the upper end of the rear leg 324 will cause the linkmember 330 to open relative to the rear leg member 324 andsimultaneously cause the pivot and sliding connection 310 to move fromthe right end of the slot 308 as shown in FIG. 16 toward the left orupper end thereof as shown in FIG. 17. When it is in its final openposition, the sliding pivot connection 310 will be at the upper end ofthe slot 308 and the top frame 304 and object 302 will be substantiallyhorizontal.

A seventh embodiment of a rolling stand of the present invention isindicated generally at 350 in FIGS. 19-22 and is shown with an object352 attached to it. In this embodiment, a top frame 354 has a forwardtransverse extension 356 with a slot 358 in which a pivot connection 360is located. The stand 350 has a side strut 362 with a bottom contactpoint 364 and a transverse platform extension 366. The side strut 362 ispivotally connected to another extension 368 of the top frame 354 by apivot connection 370 and the upper end of the side strut 362 emergesinto a handle 372. A rear leg 374 has a wheel 376 mounted to the lowerend thereof and a link member 378 is connected to the pivot connection360 and to a gear mechanism indicated generally at 380. In thisembodiment, the side strut 362 has an enlarged portion 381 in the areaof the gear mechanism 380. In this embodiment, the upper end of the rearleg 374 has a round toothed gear 382 securely attached to it, which maybe accomplished by having an irregular shaped hub 384 welded orotherwise attached to the leg 374, with the gear 382 having an internalconfiguration that is complementary to the shape of the hub 384 so thatit cannot rotate relative to the hub. The gear and leg 374 can rotaterelative to a pin 386 that is operatively connected the side strut 362.Thus, the gear 382 and leg 374 are capable of rotating relative to theside strut.

A toothed gear 388 is fixed to the link member 378 by a hub 390 that iscomplementary configured to the interior of the gear 388, but which isrotatable around pin 392 which is also fixed to the enlarged portion1381 of the side strut 362. The gears 388 and 382 have teeth that engageone another so that rotation of the rear leg 374 in one rotationalconnection will result in rotation of the link member 378 in theopposite direction. As shown in FIGS. 19 and 21, if the rear leg 374 isrotated in the counterclockwise direction, the link member 378 will thenbe rotated in the clockwise direction. If it is in the closed positionshown in FIG. 19, rotating the rear leg 374 in a counterclockwisedirection will cause the link member 378 to rotate in the clockwisedirection and the stand will be moved from its closed position shown inFIG. 19 to its open position in FIG. 20. The slot 358 permits somenecessary translating movement to occur when this unfolding operation.

While various embodiments of the present invention have been shown anddescribed, it should be understood that other modifications,substitutions and alternatives are apparent to one of ordinary skill inthe art. Such modifications, substitutions and alternatives can be madewithout departing from the spirit and scope of the invention, whichshould be determined from the appended claims.

Various features of the invention are set forth in the following claims.

1. A collapsible rolling stand for use with an elongated normallyhorizontally oriented object attached thereto, said stand beingsupported by a ground surface and having a front end portion and a rearend portion, and being capable of being manipulated between open andclosed positions, wherein the object is generally vertically orientedwhen the stand is closed, and wherein the object is generallyhorizontally oriented when the stand is in its open position, said standcomprising: a top frame having a generally planar portion beingconfigured to have the object secured thereto, said top frame planarportion being oriented in a generally horizontal position when saidstand is in its open position and a generally vertical position whensaid stand is moved to its closed position; a folding mechanismsupporting said top frame, including at least one handle operativelyconnected to one end portion of a pair of spaced apart elongated firstmembers that have opposite end portions that include points that contactthe ground surface and a pair of spaced apart second members each havingwheels for enabling a user to roll said stand on the ground surface,said first and second members being pivotally connected to one anotherand configured so that the weight of the object provides a substantialportion of the necessary force needed to pivot said first and secondpairs of members to further separate said forward contact point fromsaid rear wheels and move said stand from said closed position to saidopen position wherein said top frame planar portion is substantiallyhorizontal.
 2. A stand as defined in claim 1 wherein said foldingmechanism further comprises: said first members are located on each sideof said stand and are operatively connected to and pivotable relative toa rear portion of said top frame planar portion; each of said secondmembers having a pivot connection to one of said first members at apoint intermediate the ends of said first member, each second memberhaving one of said wheels connected to a rearward end portion thereofand an extension located forwardly of said pivot connection at apredetermined angle relative to the lengthwise direction of said secondmember; a link member pivotally attached to the distal end of saidextension and to said top frame planar portion; a handle connected toone of said top frame planar portion or said first members; a lockingmechanism for releasably holding said stand in at least the closedposition; wherein when said stand is in its closed position, actuatingsaid locking mechanism enables said second member to pivot about saidpivot connection causing the weight of the object to move said wheels ashort distance away from said top frame planar portion, further movementof said stand in the rearward direction causing said second members andwheel to rotate toward the rear of said stand to the open position wherethe top frame planar portion is oriented in said substantiallyhorizontal position.
 3. A stand as defined in claim 2 wherein saidhandle comprises a cross member that extends between and is connected toboth of said first members.
 4. A stand as defined in claim 3 whereinsaid cross member is positioned at an elevation below said top frameplanar portion and has a curved shape upwardly from each of said firstmembers.
 5. A stand as defined in claim 2 wherein said first membershave a generally transverse downward extension beyond said pivotconnection to said top frame member, with said handle being connected tothe ends of each downward extension.
 6. A stand as defined in claim 1wherein said first members and said handle are an integrally formedunitary structure.
 7. A stand as defined in claim 2 wherein saidpredetermined angle is within the range of about 40 to about 90 degrees.8. A stand as defined in claim 2 wherein said locking mechanismcomprises a sliding pin having an operating knob operatively attached toone of said first and second members that is configured to operativelyengage the other of said first and second members when said stand is inat least its closed position.
 9. A stand as defined in claim 8 whereinsaid sliding pin is biased toward engagement.
 10. A stand as defined inclaim 2 wherein said first members have a generally transverseextensions at said ground engaging opposite ends and at least one frontend bridge interconnecting said opposite ends.
 11. A collapsible rollingstand for use with an elongated normally horizontally oriented heavyobject attached thereto, said stand being supported by a ground surfaceand having a front end portion and a rear end portion, and being capableof being manipulated between open and closed positions, wherein theobject is generally vertically oriented when the stand is closed, andwherein the object is generally horizontally oriented when the stand isin its open position, said stand comprising: a top frame having agenerally planar portion being configured to have the object securedthereto, said top frame planar portion being oriented in a generallyhorizontal position when said stand is in its open position and agenerally vertical position when said stand is moved to its closedposition; a folding mechanism supporting said top frame, including atleast one handle operatively connected to one end portion of a pair ofspaced apart elongated first members that have opposite end portionsthat include points that contact the ground surface and a pair of spacedapart second members each having wheels for enabling a user to roll saidstand on the ground surface, said first and second members beingpivotally connected to one another and configured so that the weight ofthe object provides a substantial portion of the necessary force neededto pivot said first and second pairs of members to further separate saidforward contact point from said rear wheels and move said stand fromsaid closed position to said open position wherein said top frame planarportion is substantially horizontal; said folding mechanism furthercomprises: said first members are located on each side of said stand andare operatively connected to and pivotable relative to a rear portion ofsaid top frame planar portion; each of said second members having apivot connection to one of said first members at a point intermediatethe ends of said first member, each second member having one of saidwheels connected to a rearward end portion thereof and an extensionlocated forwardly of said pivot connection at a predetermined anglerelative to the lengthwise direction of said second member; a linkmember pivotally attached to the distal end of said extension and tosaid top frame planar portion; at least one handle connected to one ofsaid top frame planar portion or said first members; a locking mechanismfor releasably holding said stand in at least the closed position; saidfirst members have a generally transverse extensions at said groundengaging opposite ends and at least one front end bridge interconnectingsaid opposite ends; wherein a cross brace interconnects said firstmembers adjacent the junction of said first members and said transverseextensions, said transverse extensions, front end bridge and cross bracedefining a carrying shelf; a sheet of support material substantiallycovering said shelf and a portion of said first members adjacent saidtransverse extensions; wherein when said stand is in its closedposition, actuating said locking mechanism enables said second member topivot about said pivot connection causing the weight of the object tomove said wheels a short distance away from said top frame planarportion, further movement of said stand in the rearward directioncausing said second members and wheel to rotate toward the rear of saidstand to the open position where the top frame planar portion isoriented in said substantially horizontal position.
 12. A stand asdefined in claim 1 wherein the object is a portable circular saw.
 13. Astand as defined in claim 1 further comprising a spring for biasing saidstand toward its closed position when in its open position, such that anoperator is not required to exert more than a small force to move saidstand to its closed position.
 14. A stand as defined in claim 13 whereinsaid small force is a small fraction of the weight of the object.
 15. Astand as defined in claim 13 wherein said spring is substantiallyunloaded when the stand is in its closed position.
 16. A stand asdefined in claim 13 wherein said spring is a tension spring having oneend connected to said second member and its other end connected to saidfirst member, said spring being loaded into tension as said stand movestoward its open position.
 17. A stand as defined in claim 1 wherein saidtop frame planar portion comprises two side frame members and two endframe members interconnected in a generally planar rectangularconfiguration.
 18. A stand as defined in claim 2 further comprising atleast one stop member attached to each second member for contacting saidfirst member limiting the pivoting movement there between during openingof said stand so that said top planar portion is held in said generallyhorizontal position.
 19. A collapsible rolling stand for an elongatednormally horizontally oriented heavy object attached thereto, said standbeing supported by a ground surface and having a front end portion and arear end portion, and being capable of being manipulated between openand closed positions, wherein the object is generally verticallyoriented when the stand is closed, and wherein the object is generallyhorizontally oriented when the stand is in its open position, said standcomprising: a top frame portion generally defining a plane and beingconfigured to have the object secured thereto, said top frame portionbeing oriented in a generally horizontal position when said stand is inits open position and a generally vertical position when said stand ismoved to its closed position; a main side strut on each side of saidstand pivotally connected to a rear portion of said top frame portion,said side strut extending toward the ground surface and having a groundengaging front contact point; a rear leg having a pivotal connection forconnecting to each said side strut at a point intermediate the ends ofsaid main side strut, each rear leg having a wheel connected to a distalend portion of said rear leg and an extension located forwardly of saidpivotal connection at a predetermined angle relative to the lengthwisedirection of said rear leg; a link member pivotally attached to thedistal end of said rear leg extension and to said frame portion; atleast one handle connected to one of said top frame portion or said mainside struts; a locking mechanism for releasably holding said stand in atleast the closed position; wherein when said stand is in its closedposition, actuating said locking mechanism enables said rear leg topivot about said pivotal connection causing the weight of the object tomove said wheel a short distance away from said top frame portion,further movement of said stand in the rearward direction causing saidrear leg and wheel to rotate toward the rear of said stand to the openposition where the object is oriented in a horizontal position.
 20. Astand as defined in claim 1 wherein said top frame includes an outwardlydirected transverse extension at the front end thereof, said extensionhaving a slot on each side thereof for receiving an end of a link memberof said folding mechanism, said folding mechanism further comprising:said first members are located on each side of said stand and areoperatively connected to and pivotable relative to a rear portion ofsaid top frame portion; each of said second members having a pivotconnection to one of said first members at a point intermediate the endsof said first member, each second member having one of said wheelsconnected to a lower end portion thereof, an upper end thereof extendingupwardly beyond said pivot connection; a link member having one endpivotally attached to said upper end of said second member and anopposite end pivotally connected to and slidable in said top frameextension slot; an over center stop member attached to one of each linkmember and second member that are connected together for limiting thepivoting movement therebetween during opening of said stand so that saidtop planar portion is held in said generally horizontal position; ahandle connected to one of said top frame planar portion or said firstmembers; a locking mechanism for releasably holding said stand in atleast the closed position; wherein when said stand is in its closedposition, actuating said locking mechanism enables said second member topivot about said pivot connection causing the weight of the object tomove said wheels a short distance away from said top frame portion,further movement of said stand in the rearward direction causing saidsecond members and wheel to rotate toward the rear of said stand andsaid opposite end of said link member to slide outwardly in said slot assaid stand moves to its open position where the top frame portion isoriented in said substantially horizontal position.
 21. A stand asdefined in claim 1 wherein said folding mechanism further comprises:said first members are located on each side of said stand and areoperatively connected to and pivotable and slidable between twopositions relative to a rear portion of said top frame planar portion; alocking mechanism for at least one first member for releasably holdingsaid first member from slidably moving relative to said rear portion ofsaid top frame planar portion; each of said second members having apivot connection to one of said first members at a point intermediatethe ends of said first member, each second member having one of saidwheels connected to a lower end portion thereof and an upper end portionextending upwardly of said pivot connection; a link member having oneend pivotally attached to said upper end portion of each said secondmember and an opposite end pivotally attached to said top frame planarportion; an over center stop member attached to one of each link memberand second member that are connected together for limiting the pivotingmovement therebetween during opening of said stand so that said topplanar portion is held in said generally horizontal position; a handleconnected to one of said top frame planar portion or said first members;wherein when said stand is in its closed position, actuating saidlocking mechanism enables said second member to pivot about said pivotconnection causing the weight of the object to move said wheels a shortdistance away from said top frame planar portion, further movement ofsaid stand in the rearward direction causing said second members andwheel to rotate toward the rear of said stand to the open position wherethe top frame planar portion is oriented in said substantiallyhorizontal position.
 22. A stand as defined in claim 21 wherein saidfirst and second positions are the closed and open positions of saidstand.
 23. A stand as defined in claim 1 wherein said top frame includesan outwardly directed transverse extension at the front end thereof,said extension having a slot on each side thereof for receiving an endof a link member of said folding mechanism, said folding mechanismfurther comprising: said first members are located on each side of saidstand and are operatively connected to and pivotable relative to a rearportion of said top frame portion; each of said second members having apivot connection to one of said first members at a point intermediatethe ends of said first member, each second member having one of saidwheels connected to a lower end portion thereof, an upper end thereofextending upwardly beyond said pivot connection; a pair of first linkmembers, each having a first end pivotally attached to said upper end ofsaid second member and a second end pivotally connected to a first endof a second link member; a pair of second link members, each having afirst end pivotally connected to said second end of said first linkmember and to the first end of a third link member and a second endpivotally connected to and slidable in said top frame extension slot; apair of third link members, each having a first end pivotally connectedto said first end of said second link member and pivotally connected tosaid second end of said first link member, said third link member havinga second end pivotally connected to said ground contact end of saidfirst member; a handle connected to one of said top frame planar portionor said first members; a locking mechanism for releasably holding saidstand in at least the closed position; wherein when said stand is in itsclosed position, actuating said locking mechanism enables said secondmembers to pivot about said pivot connection causing the weight of theobject to move said second members and wheels away from said top frame,said pivoting movement of second members in the rearward directioncausing said upper end of said second members to move said first linkmembers forwardly and move the first end of said second and third linkmembers forwardly while simultaneously moving said second end of saidsecond link members downwardly in said slots as said stand moves to itsopen position where the top frame planar portion is oriented in saidsubstantially horizontal position.
 24. A stand as defined in claim 1wherein said folding mechanism further comprises: said first members arelocated on each side of said stand and are operatively connected to andpivotable relative to a rear portion of said top frame portion; each ofsaid second members having a pivot connection to one of said firstmembers at a point intermediate the ends of said first member, eachsecond member having one of said wheels connected to a lower end portionthereof, an upper end thereof extending upwardly beyond said pivotconnection; a pair of first link members, each having a first endpivotally connected to and slidable relative to said upper end of saidsecond member and a second end pivotally connected to first end portionof a second link member; a pair of second link members, each having afirst end pivotally connected to said second end of said first linkmember and to the first end of a third link member and a second endpivotally connected to said top frame; a pair of third link members,each having a first end pivotally connected to said first end of saidsecond link member and pivotally connected to said second end of saidfirst link member and to said second end of said first link member, saidthird link member having a second end pivotally connected to said groundcontact end of said first member; a handle connected to one of said topframe planar portion or said first members; a locking mechanism forreleasably holding said stand in at least the closed position; whereinwhen said stand is in its closed position, actuating said lockingmechanism enables said second members to pivot about said pivotconnection causing the weight of the object to move said second membersand wheels away from said top frame, said pivoting movement of saidsecond member in the rearward direction causing said upper end of saidsecond members to move said first link members forwardly and move thefirst end of said second and third link members forwardly whilesimultaneously sliding said upper end of said second members rearwardlyalong said first link member as said stand moves to its open positionwhere the top frame planar portion is oriented in said substantiallyhorizontal position.
 25. A stand as defined in claim 1 wherein said topframe has a pair of horizontal slots located on opposite sides of thefront thereof, said folding mechanism further comprises: said firstmembers are located on each side of said stand and are operativelyconnected to and pivotable relative to a rear portion of said top frameplanar portion, said first members having an enlarged portion at anintermediate point along their length; each of said second membershaving a pivot connection to one of said first members at or near saidenlarged portion of said first member, each second member having one ofsaid wheels connected to a rearward end portion thereof and a firsttoothed gear fixed thereto, said first gear having a center openingthrough which a first pivot pin is attached to said first member,thereby enabling said second member and first toothed gear to pivotaround said pivot pin; a pair of link members, each having a first endpivotally attached to a second pin secured to said first member at ornear said enlarged portion and a second end pivotally attached to saidtop frame, each link member having a second toothed gear fixed thereto,said second gear having a center opening through which a second pivotpin is attached to said first member, thereby enabling said secondmember and second gear to pivot around said second pivot pin, each ofsaid link members having a second end pivotally connected to said topframe slot; said teeth of first and second gears engaging each other; ahandle connected to one of said top frame planar portion or said firstmembers; a locking mechanism for releasably holding said stand in atleast the closed position; wherein when said stand is in its closedposition, actuating said locking mechanism enables said second member topivot about said pivot connection causing the weight of the object tomove said wheels away from said top frame planar portion, the movementof said stand in the rearward direction causing said second members andwheels to rotate toward the rear of said stand toward the open position,said engaged gears causing said link members to rotate in a directionopposite the rotation of said second member to the open position wherethe top frame planar portion is oriented in said substantiallyhorizontal position.
 26. A collapsible rolling stand for use with anelongated normally horizontally oriented heavy object attached thereto,said stand being supported by a ground surface and having a front endportion and a rear end portion, and being capable of being manipulatedbetween open and closed positions, wherein the object is generallyvertically oriented when the stand is closed, and wherein the object isgenerally horizontally oriented when the stand is in its open position,said stand comprising: a top frame portion being configured to have theobject secured thereto, said top frame portion being oriented in agenerally horizontal position when said stand is in its open positionand a generally vertical position when said stand is moved to its closedposition; a folding mechanism supporting said top frame portion,including at least one handle operatively connected to one end portionof a pair of spaced apart elongated first members that have opposite endportions that include points that contact the ground surface and a pairof spaced apart second members each having wheels for enabling a user toroll said stand on the ground surface, said first and second membersbeing pivotally connected to one another and configured so that theweight of the object provides a substantial portion of the necessaryforce needed to pivot said first and second pairs of members to furtherseparate said forward contact point from said rear wheels and move saidstand from said closed position to said open position wherein said topframe portion is substantially horizontal, said first and second membersbeing configured so that the weight of the object provides a substantialportion of the necessary force needed to pivot said first and secondpairs of members to move said stand from said open position to saidclosed position wherein said top frame planar portion is in a generallyvertical orientation.
 27. A collapsible rolling stand for use with anelongated normally horizontally oriented object attached thereto, saidstand being supported by a ground surface and having a front end portionand a rear end portion, and being capable of being manipulated betweenopen and closed positions, wherein the object is generally verticallyoriented when the stand is moved to its closed position, and wherein theobject is generally horizontally oriented when the stand is in its openposition, said stand comprising: a folding mechanism supporting theobject, including at least one handle operatively connected to one endportion of a pair of spaced apart first members that have opposite endportions that include points that contact the ground surface ends and apair of spaced apart second members each having wheels for enabling auser to roll said stand on the ground surface, said first and secondmembers being pivotally connected to one another and configured so thatthe weight of the object provides a substantial portion of the necessaryforce needed to pivot said first and second pairs of members to furtherseparate said forward contact point from said rear wheels and move saidstand from said closed position to said open position wherein the objectis substantially horizontal.